极性诱导季铵盐表面活性剂改性膨润土的制备及净水特性

Synthesis and Water Purification Properties of Bentonite Modified with Polar-Inducing Quaternary Surfactant

为高效、经济及绿色地处理难降解有机废水,设想引入极性诱导效应,提高季铵盐表面活性剂对膨润土的功能改性效率,从而获得性能更优的改性膨润土材料,用于对难降解有机废水的吸附处理。设计一种“来源便利”的极性诱导季铵盐表面活性剂(3-氯-2-羟丙基十二烷基二甲基氯化铵,C12-CHDMAC),制备新型改性膨润土材料,即C12-改性膨润土。结果表明:①所得C12-改性膨润土所含表面活性剂关键元素C、H、N含量分别为23.51%、5.72%和2.65%,远高于常规类似结构季铵盐表面活性剂改性膨润土所含对应元素含量(分别为14.56%、3.99%和1.58%),成功获得了功能改性率更高的改性膨润土材料。②以吸附有机染料废水为例,考察C12-改性膨润土作为吸附剂吸附处理难降解有机废水的能力,其吸附容量为活性炭的203.21倍,具有较强的吸附净水能力。③通过系列化吸附动力学、吸附热力学和现代仪器分析技术,深入探究了C12-改性膨润土吸附处理难降解有机废水的作用行为,提出了相关作用机制的理论解释。④制备过程中产生的剩余滤液,具备直接回收重复利用或直接功能化使用的特性,以此可提高原料利用率,并杜绝生产废液的“二次污染”,因而所设计的制备工艺具有经济高效、绿色环保的优势。研究显示,C12-改性膨润土可以高效、经济及绿色地吸附处理难降解有机废水,应用前景良好。

In order to treat recalcitrant organic wastewater efficiently,economically,and environmentally,the concept of introducing polarity-inducing effects was envisaged.This aims to improve the functional modification efficiency of quaternary ammonium salt surfactants on bentonite,thereby obtaining modified bentonite materials with superior performance for adsorption treatment of recalcitrant organic wastewater.A‘conveniently sourced’polarity-inducing quaternary ammonium salt surfactant(3-chloro-2-hydroxypropyl-dimethylstearyl ammonium chloride,C12-CHDMAC)was designed and utilized to prepare a novel modified bentonite material termed C12-modified bentonite.The results showed that:(1)The C12-modified bentonite contained critical elements C,H,and N,with concentrations of 23.51%,5.72%and 2.65%,respectively.These concentrations significantly exceeded those in conventional structural quaternary ammonium salt surfactant-modified bentonite materials(14.56%,3.99%and 1.58%),thereby achieving higher functional modification rates.(2)Using adsorption of organic dye wastewater as an example,the adsorption capacity of C12-modified bentonite was 203.21 times that of activated carbon,highlighting its robust purification capability.(3)Through comprehensive analysis of adsorption kinetics,thermodynamics,and modern instrumental techniques,the adsorption behavior of C12-modified bentonite in treating recalcitrant organic wastewater was thoroughly investigated,and its adsorption mechanism was explained.(4)The residual filtrate generated during the preparation process possesses characteristics suitable for direct recycling or functionalization,ensuring enhanced raw material utilization and mitigating the risk of‘secondary pollution’of production wastewater.Consequently,the designed preparation process has economic efficiency and environmental advantages.The research demonstrates that C12-modified bentonite offers promising prospects for efficient,economical,and environmentally adsorption and treatment of recalcitrant organic wastewater.